Airbag cushion exhibiting low seam usage and simultaneously high available inflation volume

ABSTRACT

The present invention relates to an airbag cushion which exhibits a low amount of seam usage (in order to attach at least two fabric panels or portions of a panel together) in correlation to an overall high amount of available inflation airspace within the cushion itself. These correlated elements are now combined for the first time in what is defined as an effective seam usage index (being the quotient of the length of overall seams on the cushions and the available inflation airspace volume). The inventive cushion must have at least one substantially straight seam and must possess an effective seam usage factor of less than about 0.11. A cushion exhibiting such a low seam usage factor and also comprising an integrated looped pocket for the disposition of an inflator can is also provided as well as an overall vehicle restraint system comprising the inventive airbag cushion.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a divisional of pending U.S. patentapplication Ser. No. 09/813,632, filed on Mar. 21, 2001, which is acontinuation of U.S. patent application Ser. No. 09/365,372, filed onJul. 30, 1999, and issued on Oct. 29, 2002, to Keshavaraj as U.S. Pat.No. 6,472,033. These references are all hereby incorporated herein intheir entirety by specific reference thereto.

FIELD OF THE INVENTION

[0002] The present invention relates to an airbag cushion which exhibitsa low amount of seam usage (in order to attach at least two fabricpanels or portions of a panel together) in correlation to an overallhigh amount of available inflation airspace within the cushion itself.These correlated elements are now combined for the first time in what isdefined as an effective seam usage index (being the quotient of thelength of overall seams on the cushions and the available inflationairspace volume). The inventive cushion must have at least onesubstantially straight seam and must possess an effective seam usagefactor of less than about 0.11. A cushion exhibiting such a low seamusage factor and also comprising an integrated looped pocket for thedisposition of an inflator can is also provided as well as an overallvehicle restraint system comprising the inventive airbag cushion.

BACKGROUND OF THE PRIOR ART

[0003] Inflatable protective cushions used in passenger vehicles are acomponent of relatively complex passive restraint systems. The mainelements of these systems are: an impact sensing system, an ignitionsystem, a propellant material, an attachment device, a system enclosure,and an inflatable protective cushion. Upon sensing an impact, thepropellant is ignited causing an explosive release of gases filing thecushion to a deployed state which can absorb the impact of the forwardmovement of a body and dissipate its energy by means of rapid venting ofthe gas. The entire sequence of events occurs within about 30milliseconds. In the undeployed state, the cushion is stored in or nearthe steering column, the dashboard, in a door, or in the back of a frontseat placing the cushion in close proximity to the person or object itis to protect.

[0004] Inflatable cushion systems commonly referred to as air bagsystems have been used in the past to protect both the operator of thevehicle and passengers. Systems for the protection of the vehicleoperator have typically been mounted in the steering column of thevehicle and have utilized cushion constructions directly deployabletowards the driver. These driver-side cushions are typically of arelatively simple configuration in that they function over a fairlysmall well-defined area between the driver and the steering column. Onesuch configuration is disclosed in U.S. Pat. No. 5,533,755 to Nelsen etal., issued Jul. 9, 1996, the teachings of which are incorporated hereinby reference.

[0005] Inflatable cushions for use in the protection of passengersagainst frontal or side impacts must generally have a more complexconfiguration since the position of a vehicle passenger may not be welldefined and greater distance may exist between the passenger and thesurface of the vehicle against which that passenger might be thrown inthe event of a collision. Prior cushions for use in such environmentsare disclosed in U.S. Pat. No. 5,520,416 to Bishop, issued May 28, 1996;U.S. Pat. No. 5,454,594 to Krickl issued Oct. 3, 1995; U.S. Pat. No.5,423,273 to Hawthorn et al. issued Jun. 13, 1995; U.S. Pat. No.5,316,337 to Yamaji et al. issued May 31, 1994; U.S. Pat. No. 5,310,216to Wehner et al. issued May 10, 1994; U.S. Pat. No. 5,090,729 toWatanabe issued Feb. 25, 1992; U.S. Pat. No. 5,087,071 to Wallner et al.issued Feb. 11, 1992; U.S. Pat. No. 4,944,529 to Backhaus issued Jul.31, 1990; and U.S. Pat. No. 3,792,873 to Buchner et al. issued Feb. 19,1974, all of which are incorporated herein by reference.

[0006] The majority of commercially used restraint cushions are formedof woven fabric materials utilizing multifilament synthetic yarns ofmaterials such as polyester, nylon 6 or nylon 6,6 polymers.Representative fabrics for such use are disclosed in U.S. Pat. No.4,921,735 to Bloch issued May 1, 1990; U.S. Pat. No. 5,093,163 toKrummheuer et al. issued Mar. 3, 1992; U.S. Pat. No. 5,110,666 to Menzelet al. issued May 5, 1992; U.S. Pat. No. 5,236,775 to Swoboda et al.Aug. 17, 1993; U.S. Pat. No. 5,277,230 to Sollars, Jr. issued Jan. 11,1994; U.S. Pat. No. 5,356,680 to Krummheuer et al. Oct. 18, 1994; U.S.Pat. No. 5,477,890 to Krummheuer et al. issued Dec. 26, 1995; U.S. Pat.No. 5,508,073 to Krummheuer et al., issued Apr. 16, 1996; U.S. Pat. No.5,503,197 to Bower et al. issued Apr. 2, 1996 and U.S. Pat. No.5,704,402 to Bowen et al. issued Jan. 6, 1998, all of which areincorporated herein by reference.

[0007] As will be appreciated, the permeability of the cushion structureis an important factor in determining the rate of inflation andsubsequent rapid deflation following the impact event. In order tocontrol the overall permeability of the cushion, it may be desirable touse differing materials in different regions of the cushion. Thus, theuse of several fabric panels in construction of the cushion may prove tobe a useful design feature. The use of multiple fabric panels in thecushion structure also permits the development of relatively complexthree dimensional geometries which may be of benefit in the formation ofcushions for passenger side applications wherein a full bodied cushionis desired. While the use of multiple fabric panels provides severaladvantages in terms of permeability manipulation and geometric design,the use of multiple fabric panels for use in passenger side restraintcushions has historically required the assembly of panels havingmultiple different geometries involving multiple curved seams.

[0008] As will be appreciated, an important consideration in cuttingpanel structures from a base material is the ability to maximize thenumber of panels which can be cut from a fixed area through close-packednesting of the panels. It has been found that minimizing the number ofdifferent geometries making up panels in the cushion and usinggeometries with substantially straight line perimeter configurationsgenerally permits an enhanced number of panels to be cut from the basematerial. The use of panels having generally straight line profiles hasthe added benefit of permitting the panels to be attached to one anotherusing substantially straight seams or be substantially formed during theweaving process using a jacquard or dobby loom. For the purposes of thisinvention, the term “seam” is to be understood as any point ofattachment between different fabric panels or different portions of thesame fabric panel. Thus, a seam may be sewn (such as with thread),welded (such as by ultrasonic stitching), woven (such as on a jacquardor dobby loom, as merely examples), and the like. The key issueregarding seam length within this invention pertains to the ability toform a high available inflation airspace volume cushion with the lowestamount of labor needed. Since sewing, welding, etc., procedures toconnect panels or portions of panels greatly increases the timenecessary to produce airbag cushions, it is highly desirable to reducethe labor time which can be accomplished through the reduction in thelength of seams required. Substantially straight seam configurationsthus provide more cost-effective methods of producing such airbags.

[0009] However, even with the utilization of substantially straightseams to produce airbags cushions, a problem still resides in the needfor labor-intensive cutting and sewing operations for large-scalemanufacture. There remains a need then to reduce the amount of time toproduce airbag cushions while simultaneously providing the greatestamount of fabric to allow for a sufficient volume of air (gas) toinflate the target airbag cushion during an inflation event (hereindescribed as “available inflation airspace””). Such a desired method andproduct has not been available, particularly for passenger-side airbagswhich, as noted previously, require greater amounts of fabric for largervolumes of air (gas) to provide the greatest amount of protection areato a passenger. With greater amounts of fabric needed, generally thishas translated into the need for longer seams to connect and attachfabric panels, which in turn translates into greater amounts of timeneeded for sewing, and the like, operations. Thus, a need exists toproduce high available inflation airspace volume airbag cushions withminimal requirements in seam lengths to manufacture the overall cushionproduct. The prior art has not accorded any advancements or evendiscussions to this effect.

SUMMARY OF THE INVENTION

[0010] In view of the foregoing, it is a general object of the presentinvention to provide a cost-effective, easy to manufacture airbagcushion for utilization within a vehicle restraint system. The termvehicle restraint system is intended to mean both inflatable occupantrestraining cushion and the mechanical and chemical components (such asthe inflation means, ignition means, propellant, and the like). It is amore particular object of the present invention to provide a vehiclerestraint system wherein the target airbag cushion preferably requiresall substantially straight seams to attach its plurality fabriccomponents together (although as noted above, other configured seams mayalso be used as long the overall required effective seam usage factor ismet). A further object of this invention is to provide aneasy-to-assemble airbag cushion which is minimally labor-intensive tomanufacture, which also comprises an integrated looped pocket for thedisposition of an inflator can within the airbag cushion. It is still afurther object of this invention to provide a vehicle restraint systemcomprising an airbag cushion which provides the maximum amount ofavailable inflation airspace volume simultaneously with the lowestlength of seam (or seams) necessary to manufacture the cushion. Anotherobject of the invention is to provide a method of making a low costairbag cushion (due to low levels of labor required to sew the componentparts together) of simple and structurally efficient design.

[0011] To achieve these and other objects and in accordance with thepurpose of the invention, as embodied and broadly described herein, thepresent invention provides an airbag cushion having at least onesubstantially straight seam, wherein said airbag cushion possesses aneffective seam usage factor of less than about 0.11, wherein said seamusage factor is derived from a seam usage index which concerns (and isdefined as) the quotient of the total length of all seams present withinthe airbag cushion (measured in meters) over the total volume ofavailable inflation airspace within the airbag cushion (measured inliters). As noted above, the seam itself may be applied by any wellknown operation including, but not limited to, thread-stitching,ultrasonic stitching, and the like, or could be woven within the fabricon a jacquard or dobby loom, and the like. The term “available inflationairspace,” as eluded to above, connotes the volume within which air(gas) would be transferred from an inflation assembly to the airbagcushion during inflation, and thus a consequent inflation event. Such anairbag cushion must generally have at least one substantially straightseam, although, preferably, each seam possesses such a specificconfiguration. In order to produce such a specific airbag cushion, infact, it is evident that the amount of sewing, stitching, and the like,required to form the end-product must be very low A curved seam,although possible in this invention, requires potentially longer lengthsof thread, etc., in order to attach the different fabric components ofthe target cushion. As a result, the utilization of curved, or othernon-straight seams, should be minimized.

[0012] The effective seam usage factor (as defined within thecorrelating seam usage index formula, above) for the inventive airbagcushion then is preferably less than about 0.10, more preferably lessthan 0.09, still more preferably less than 0.07, even more preferablyless than 0.06, and most preferably lower than 0.05. Thus, the volume ofavailable inflation airspace within the airbag cushion should be asgreat as possible with the length of seam reduced to its absoluteminimum.

[0013] A one-piece construction will generally have a relatively lowavailable inflation airspace volume, although the length of the totalnumber of seams may be quite low; a driver-side airbag will generallyconsist of many seams (of relatively large overall length), particularlycurved seams, and a correlative relatively low volume of availableairspace; and the prior art passenger-side airbags require complexsewing operations with numerous and rather long seams. Although theavailable inflation airspace volume in such passenger-side airbags israther large, the total length of all the utilized seams is generallytoo great to meet the aforementioned effective seam usage factor withinthe index.

[0014] The present invention also provides an airbag cushion possessingthe required effective seam usage factor which also comprises a loopedpocket for introduction of the inflator can of an inflator assembly. Inthe most preferred embodiment one large body panel is utilized havingtwo mirror-image portions which, when folded over along the middle ofthe fabric panel, the boundaries of both portions are aligned. Onesubstantially straight seam is then utilized to seal the adjacent (andsimilarly configured) side to the already-folded side and two openingwill remain. The large opening is then covered by one panel ofrectilinear shape; the small opening (opposite the large opening) willhave extra fabric which can be overlapped (to provide extra reinforcingfabric at the point of potential inflation) and sewn to form the desiredpocket in which to dispose the inflation can. This embodiment isdiscussed below in greater detail.

[0015] Additional objects and advantages of the invention will be setforth in part in the description which follows, and in part will beobvious from the description, or may be learned by practice for theinvention. It is to be understood that both the foregoing generaldescription and the following detailed description of preferredembodiments are exemplary and explanatory only, and are not to be viewedas in any way restricting the scope of the invention as set forth in theclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings, which are incorporated in andconstitute a part of this specification, illustrate several potentiallypreferred embodiments of the invention (the groupings of FIGS. 1-9,10-18 and 19-26 each represent individual preferred embodiments) andtogether with the description serve to explain the principles of theinvention wherein:

[0017]FIG. 1 is an aerial view of a portion of a fabric web with linesindicating the specific preferred locations for cutting to form two setsof fabric panels to manufacture two separate inventive cushions, eachfor the inclusion within a vehicle restraint system configured within amodule which is stored substantially vertically.

[0018]FIG. 2 is an aerial view of a preferred cut fabric panel withsecond and third smaller preferred cut panels connected thereto.

[0019]FIG. 3 is an aerial view of the connected preferred cut fabricpanels showing the first folding step in producing the mouth portion ofthe target cushion.

[0020]FIG. 4 is an aerial view of the connected preferred cut fabricpanels showing the second folding step in producing the mouth portion ofthe target cushion.

[0021]FIG. 5 is an aerial view of the connected preferred cut fabricpanels showing the third folding step in producing the mouth portion ofthe target cushion as well as the entire connected fabric panelcomposite folded over and connected to itself.

[0022]FIG. 6 is an aerial view of the preferred cut fabric front panelof the target cushion.

[0023]FIG. 7 is a front view of the finished target cushion showing thepreferred front panel and the substantially straight seams connectingthe front panel to the remaining preferred cut fabric panels.

[0024]FIG. 8 is a side view of the finished, unfolded, and non-inflated,target cushion.

[0025]FIG. 9 is a cut-away side view of a vehicle for transporting anoccupant illustrating the deployment of an inflatable restraint cushionwithin a vehicle restraint system according to the present invention.

[0026]FIG. 10 is an aerial view of a portion of a fabric web with linesindicating the specific preferred locations for cutting to form two setsof fabric panels to manufacture two separate inventive cushions, eachfor the inclusion within a vehicle restraint system configured within amodule which is stored substantially horizontally.

[0027]FIG. 11 is an aerial view of a preferred cut fabric panel withsecond and third smaller preferred cut panels connected thereto.

[0028]FIG. 12 is an aerial view of the connected preferred cut fabricpanels showing the first folding step in producing the mouth portion ofthe target cushion.

[0029]FIG. 13 is an aerial view of the connected preferred cut fabricpanels showing the second folding step in producing the mouth portion ofthe target cushion.

[0030]FIG. 14 is an aerial view of the connected preferred cut fabricpanels showing the third folding step in producing the mouth portion ofthe target cushion as well as the entire connected fabric panelcomposite folded over and connected to itself.

[0031]FIG. 15 is an aerial view of the preferred cut fabric front panelof the target cushion.

[0032]FIG. 16 is a front view of the finished target cushion showing thepreferred front panel and the substantially straight seams connectingthe front panel to the remaining preferred cut fabric panels.

[0033]FIG. 17 is a side view of the finished, unfolded, andnon-inflated, target cushion.

[0034]FIG. 18 is a cut-away side view of a vehicle for transporting anoccupant illustrating the deployment of an inflatable restraint cushionwithin a vehicle restraint system according to the present invention.

[0035]FIG. 19 is an aerial view of a portion of a fabric web with linesindicating the specific preferred locations for cutting to form two setsof fabric panels to manufacture two separate inventive cushions, eachwhich provide means for an integrated mouth to form a pocket for thedisposition of an inflation can therein.

[0036]FIG. 20 is an aerial view of a preferred cut fabric panel withsecond and third smaller preferred cut panels connected thereto.

[0037]FIG. 21 is an aerial view of the connected preferred cut fabricpanels showing the entire connected fabric panel composite folded overand connected to itself.

[0038]FIG. 22 is an aerial view of the preferred cut fabric front panelof the target cushion.

[0039]FIG. 23 is a front view of the finished target cushion showing thepreferred front panel and the substantially straight seams connectingthe front panel to the remaining preferred cut fabric panels.

[0040]FIG. 24 is a top view of the finished, unfolded and non-inflated,target cushion.

[0041]FIG. 25 is a side view of the finished, unfolded and non-inflated,target cushion including the integrated mouth structure for thedisposition of an inflation can therein.

[0042]FIG. 26 is a cut-away side view of a vehicle for transporting anoccupant illustrating the deployment of an inflatable restraint cushionwithin a vehicle restraint system according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0043] Reference will now be made in detail to potentially preferredembodiments of the invention, examples of which have been illustrated inthe accompanying drawings. It is to be understood that it is in no wayintended to limit the invention to such illustrated and describedembodiments. On the contrary, it is intended to cover all alternatives,modifications and equivalents as may be included within the true spiritand scope of the invention as defined by the appended claims andequivalents thereto.

[0044] Turning now to the drawings, wherein like elements are denoted bylike reference numerals throughout the various views, in FIG. 1 there isshown a fabric web 10, wherein eight fabric panels to be cut 12, 14, 16,18, 20, 22, 24, and 26 have been outlined. Also, specific fabrics piecesto be removed and slits 28, 30, 32 within the two largest fabric panels12, 14 are outlined as well. The fabric web 10 in this specific examplecomprised nylon 6,6, 630 denier yarns, woven on a jacquard loom into afabric 10 comprising 41 picks by 41 ends per inch.

[0045] In FIG. 2, two smaller preferred fabric panels 16, 18 have beenconnected to one preferred large fabric panel 12 by substantiallystraight seams 34, 36, 38, 40. The composite fabric structure now hastwo small fabric portions 39, 41 uncovered by the two smaller fabricpanels 16, 18. The free space 30 remains and an imaginary straight line42 denotes the future fold line within the fabric composite of thefabric panels 12, 16, 18.

[0046] In FIG. 3, tie-rods 42, 44 have been placed over the small fabricportions 39, 41 parallel to the seams 38, 40, and the fabric portions39, 41 have been folded back in a manner to form a right angle at thepoint of contact between the two portions 39, 41.

[0047] In FIG. 4, the small fabric portions 39, 41 have been folded overonce again and seams 35, 37 have been produced to connect the fabricportions 39, 41 to themselves and to the smaller fabric panels 16, 18.The folded over fabric portions 39, 41 provide reinforcement in order towithstand inflation pressures at the mouth opening of the cushion.

[0048] In FIG. 5, the fabric panel 12 has been folded over imaginaryline 42 (in half) leaving one smaller fabric panel 16 in view (the otheris not illustrated as it is now located on the bottom portion of fabricpanel 12 directly beneath smaller fabric panel 18). A seam 46 connectsfabric panel 12 to itself and also connects the smaller fabric panels16, 18 both to the larger panel 12 and to themselves. Upon unfolding ofthe connected composite, the non-connected ends of the panel 12 willform the same shape as the front panel 24 of FIG. 6. FIG. 7 then showsthe seam 48 needed to sew the non-connected ends of the large panel 12(of FIG. 5), and FIG. 8 provides a side view of the finished cushion 50after all the connection through seams 38, 42, 34, 46 have been made.

[0049]FIG. 9 shows a fully deployed inflatable restraint cushion 50 inopposing relation to an occupant 52 located on the front seat 54 of avehicle 56 such as an automobile, airplane, and the like. As shown, thecushion 50 may be outwardly deployed from the dash panel 57 through aninflation means 58 from a position directly opposite the occupant 52. Itis to be understood, however, that the cushion 50 may likewise bedeployed from any other desired location in the vehicle 56 including thesteering wheel (not illustrated), the vehicle side panels (notillustrated), the floor (not illustrated), or the backrest of the frontseat 54 for disposition in opposing relation to a rear passenger (notillustrated).

[0050] In FIG. 10 there is shown a fabric web 110, wherein eight fabricpanels to be cut 112, 114, 116, 118, 120, 122, 124, and 126 have beenoutlined. Also, specific slits 128, 129, 130, 32 within the two largestfabric panels 112, 114 are outlined as well. The fabric web 110 in thisspecific example comprised nylon 6,6, 630 denier yarns, woven on ajacquard loom into a fabric 110 comprising 41 picks by 41 ends per inch.

[0051] In FIG. 11, two smaller preferred fabric panels 116, 118 havebeen connected to one preferred large fabric panel 112 by substantiallystraight seams 144, 146, 148. The composite fabric structure now has twosmall fabric portions 131, 150, 152 uncovered by the two smaller fabricpanels 116, 118. An imaginary straight line 142 denotes the future foldline within the fabric composite of the fabric panels 112, 116, 118,which is noticeably off-center in order to ultimately allow for the bagto be deployed at an angle from a horizontally disposed dashboard (notillustrated).

[0052] In FIG. 12, tie-rods 153, 155 have been placed over the smallfabric portions 150, 152 and have been folded back over the tie-rods153, 155 as shown, folded again, as in FIG. 13, and connected tothemselves by seams 152, 156. The folded over fabric portions 150, 152provide reinforcement in order to withstand inflation pressures at themouth opening of the cushion.

[0053] In FIG. 14, the fabric panel 112 has been folded over imaginaryline 142 leaving one smaller fabric panel 116 in view (the other is notillustrated as it is now located on the bottom portion of fabric panel112 directly beneath smaller fabric panel 118). A seam 158 connectsfabric panel 112 to itself and also connects the smaller fabric panels116, 118 both to the larger panel 112 and to themselves. Upon unfoldingof the connected composite, the non-connected ends of the panel 112 willform the same shape as the front panel 124 of FIG. 15. FIG. 16 thenshows the seam 159 needed to sew the non-connected ends of the largepanel 112 (of FIG. 14), and FIG. 17 provides a side view of the finishedcushion 160.

[0054]FIG. 18 shows a fully deployed inflatable restraint cushion 160 inopposing relation to an occupant 162 located on the front seat 164 of avehicle 166 such as an automobile, airplane, and the like. As shown, thecushion 160 may be outwardly deployed from the dash panel 167 through aninflation means 168 from a position directly opposite the occupant 162.It is to be understood, however, that the cushion 160 may likewise bedeployed from any other desired location in the vehicle 166 includingthe steering wheel (not illustrated), the vehicle side panels (notillustrated), the floor (not illustrated), or the backrest of the frontseat 164 for disposition in opposing relation to a rear passenger (notillustrated).

[0055] In FIG. 19 there is shown a fabric web 210, wherein eight fabricpanels to be cut 212, 214, 216, 218, 220, 222, 224, and 226 have beenoutlined. Also, specific fabrics pieces to be removed and slits 228,230, 232 within the two largest fabric panels 212, 214 are outlined aswell. The fabric web 210 in this specific example comprised nylon 6,6,630 denier yarns, woven on a jacquard loom into a fabric 210 comprising41 picks by 41 ends per inch.

[0056] In FIG. 20, two smaller preferred fabric panels 216, 218 havebeen connected to one preferred large fabric panel 212 by substantiallystraight seams 234, 236, 238, 240. An imaginary straight line 242denotes the future fold line within the fabric composite of the fabricpanels 212, 216, 218.

[0057] In FIG. 21, the fabric panel 212 has been folded over imaginaryline 242 (in half) leaving one smaller fabric panel 216 in view (theother is not illustrated as it is now located on the bottom portion offabric panel 212 directly beneath smaller fabric panel 218). A seam 244connects fabric panel 212 to itself and also connects the smaller fabricpanels 216, 218 both to the larger panel 212 and to themselves. Uponunfolding of the connected composite, the non-connected ends of thepanel 212 will form the same shape as the front panel 224 of FIG. 22.FIG. 23 then shows the seam 252 needed to sew the non-connected ends ofthe large panel 212 (of FIG. 21), and FIG. 24 provides a top view of afinished cushion 246 and FIG. 25 provides a side view of a finishedcushion 250 after all the connection through seams 234, 244, 248 havebeen made.

[0058]FIG. 26 shows a fully deployed inflatable restraint cushion 260 inopposing relation to an occupant 262 located on the front seat 264 of avehicle 266 such as an automobile, airplane, and the like. As shown, thecushion 260 may be outwardly deployed from the dash panel 267 through aninflation means 268 from a position directly opposite the occupant 262.It is to be understood, however, that the cushion 260 may likewise bedeployed from any other desired location in the vehicle 266 includingthe steering wheel (not illustrated), the vehicle side panels (notillustrated), the floor (not illustrated), or the backrest of the frontseat 264 for disposition in opposing relation to a rear passenger (notillustrated).

[0059] These specific configurations and shapes provide the lowestoverall seam usage as compared to the available inflation airspacevolume. Specific measurements for each inventive cushion manufactured inthis configuration (but with different amounts of utilized fabric) arefurther described in Table 2, below.

[0060] Each of the panels utilized in these preferred embodiments may beformed from a number of materials including by way of example only andnot limitation woven fabrics, knitted fabrics, non-woven fabrics, filmsand combinations thereof. Woven fabrics may be preferred with wovenfabrics formed of tightly woven construction such as plain or panamaweave constructions being particularly preferred. Such woven fabrics maybe formed from yarns of polyester, polyamides such as nylon 6 andnylon-6,6 or other suitable material as may be known to those in theskill in the art. Multifilament yarns having a relatively low denier perfilament rating of not greater than about 1-4 denier per filament may bedesirable for bags requiring particular good foldability.

[0061] In application, woven fabrics formed from synthetic yarns havinglinear densities of about 40 denier to about 1200 denier are believed tobe useful in the formation of the airbag according to the presentinvention. Fabrics formed from yarns having linear densities of about315 to about 840 are believed to be particularly useful, and fabricsformed from yarns having linear densities in the range of about 400 toabout 650 are believed to be most useful.

[0062] While each of the panels may be formed of the same material, thepanels may also be formed from differing materials and or constructionssuch as, without limitation, coated or uncoated fabrics. Such fabricsmay provide high permeability fabric having an air permeability of about5 CFM per square foot or higher, preferably less than about 3 CFM persquare foot or less when measured at a differential pressure of 0.5inches of water across the fabric. Fabrics having permeabilities ofabout 1-3 CFM per square foot may be desirable as well. Fabrics havingpermeabilities below 2 CFM and preferably below 1 CFM in the uncoatedstate may be preferred. Such fabrics which have permeabilities below 2CFM which permeability does not substantially increase by more than afactor of about 2 when the fabric is subjected to biaxial stresses inthe range of up to about 100 pounds force may be particularly preferred.Fabrics which exhibit such characteristics which are formed by means offluid jet weaving may be most preferred, although, as noted previously,weaving on jacquard and/or dobby looms also permits seam productionwithout the need for any further labor-intensive sewing or weldingoperations.

[0063] In the event that a coating is utilized on one or more materialpanels, neoprene, silicone urethanes or disperse polyamides may bepreferred. Coatings such as dispersed polyamides having dry add onweights of about 0.6 ounces per square yard or less and more preferablyabout 0.4 ounces per square yard or less and most preferably about 0.3per square yard or less may be particularly preferred so as to minimizefabric weight and enhance foldability. It is, of course, to beunderstood that aside from the use of coatings, differentcharacteristics in various panels may also be achieved through the useof fabrics incorporating differing weave densities and/or finishingtreatments such as calendaring as may be known to those in the skill ofthe art.

[0064] While the airbag cushions according to the present invention havebeen illustrated and described herein, it is to be understood that suchcushions may also include additional components such as shape definingtethers, gas vents, and the like as may be known to those in the skillof the art.

[0065] With regard to comparable airbag cushions, the following tablepresents comparative seam usage factors for other well known andcommercially available airbag cushions. The labels used are those usedwithin Standard & Poor's DRI, a well known publication which denotesmany different types of products offered for sale to the automotiveindustry. TABLE I Seam Usage Index Factors for Comparative CommerciallyAvailable Airbag Cushions S&P DRI Number Total Length AvailableInflation Seam Usage (A/B) of Total Seams (m)(“A”) Airspace Volume(L)(“B”) Factor GM-C4 12.42 95.00 0.1307 W202 14.83 129.00 0.1150 GM420012.43 90.00 0.1381 414T 14.83 128.00 0.1159 CY 14.83 128.00 0.1159 CF16.83 128.00 0.1315

[0066] The 414T and CF bags listed above are tilted cushions for use inconjunction with relatively horizontal dashboards. The others are usedin conjunction with substantially vertically configured dashboards.

[0067] Generally, a airbag module manufacturer or automobilemanufacturer will specify what dimensions and performancecharacteristics are needed for a specific model and make of car. Thus,airbag inflation airspace volume, front panel protection area(particularly for passenger-side airbag cushions), and sufficientoverall protection for a passenger are such required specifications. Incomparison with those commercially available airbag cushions listedabove, the inventive airbag cushions which meet the same specifications(and actually exceed the overall passenger protection characteristicsversus the prior art cushions) but require less fabric, less seam lengthfor sewing operations, and thus cost appreciably less than thosecompetitive cushions. The dimensions and seam usage factors for theinventive bags (which compare with those in Table 1, above, directly,and as noted) are presented below in tabular form and are the samegeneral shape as those presented within the drawings described above(but with larger pieces of fabric panels, etc.): TABLE 2 Seam UsageIndex Factors for Inventive Airbag Cushions in Correlation to the S&PDRI Numbered Airbag Cushions Requiring Similar Dimensions andPerformance Characteristics Correlated Bags by S&P DRI Number TotalLength Available Inflation Seam Usage (A/B) of Total Seams (m)(“A”)Airspace Volume (L)(“B”) Factor GM-C4 7.56 95.00 0.0796 W202 6.90 129.000.0535 GM4200 7.20 90.00 0.0800 414T 6.90 128.00 0.0539 CY 5.35 128.000.0418 CF 6.90 128.00 0.0539

[0068] Clearly, the inventive bags, which possess the same availableinflation airspace volume and front fabric panel area as the comparativeprior art commercially available cushions (bags), require much less inthe way of total seam length, which thus correlates into overall muchlower effective seam usage factors. Furthermore, as noted above, instandard crash tests, these inventive bags (cushions) either performedas well as or outperformed their commercially available, more expensive,counterparts.

[0069] While specific embodiments of the invention have been illustratedand described, it is to be understood that the invention is not limitedthereto, since modifications may certainly be made and other embodimentsof the principals of this invention will no doubt occur to those skilledin the art. Therefore, it is contemplated by the appended claims tocover any such modifications and other embodiments as incorporate thefeatures of this invention which in the true spirit and scope of theclaims hereto.

What I claim is:
 1. A method of forming an airbag cushion exhibiting ahigh available inflation volume comprising the steps of (a) providing afirst fabric blank having a first end and a second end with two sharededges, wherein said fabric blank also compries a cut-out pattern foreventual placement of an inflation canister or attachment to aninflation assembly, and wherein said fabric blank optionally comprisesreinforcing layers of fabric attached adjacent to said cut-out pattern;(b) folding said first fabric blank of step “a” such that at least oneof said shared edges is in complete contact with itself; (c) connectingonly one of the said at least one shared edge in contact with itself toform a folded composite having a first opening and a second opening,wherein said first opening exhibits edges in a single plane and is widerthan said second opening, and wherein said second opening is saidcut-out pattern of step “a”; (d) providing a second fabric blank; and(e) connecting said second fabric blank to said edges of said firstopening of said folded composite of step “c”.
 2. The method of claim 1wherein said second opening of step “c” comprises two fabric componentswhich are subsequently connected to form a looped pocket on said airbagcushion.
 3. The method of claim 1 wherein said fabric reinforcements ofstep “a” are present.
 4. The method of claim 1 wherein said secondopening on said folded composite of step “c” Is symmetrical.
 5. Themethod of claim 1 wherein said second opening on said folded compositeof step “c” is asymmetrical.
 6. The method of claim 1 wherein saidsecond fabric blank is substantially rectangular in shape.
 7. An airbagcushion comprising at least a first fabric blank and a second fabricblank connected together through the utilization of at least two seams,wherein said airbag cushion has a first end and a second end such thatsaid first end is closed and said second end is open, wherein only oneof said at least seams is in contact with both said first end and saidsecond end.
 8. The airbag cushion of claim 7 wherein said seam incontact with both said first end and said second end is substantiallystraight.
 9. The airbag cushion of claim 7 wherein said second endcomprises a looped pocket for inflation canister disposition.
 10. Theairbag cushion of claim 7 wherein said second end exhibits a symmetricalopening for inflation assembly attachment.
 11. The airbag cushion ofclaim 7 wherein said second end exhibits an asymmetrical opening forinflation assembly attachment.
 12. A vehicle restraint system comprisingthe airbag cushion made by the method of claim
 1. 13. A vehiclerestraint system comprising the airbag cushion made by the method ofclaim
 2. 14. A vehicle restraint system comprising the airbag cushionmade by the method of claim
 3. 15. A vehicle restraint system comprisingthe airbag cushion made by the method of claim
 4. 16. A vehiclerestraint system comprising the airbag cushion made by the made by themethod of claim
 5. 17. A vehicle restraint system comprising the airbagcushion made by the method of claim
 6. 18. A vehicle restraint systemcomprising the airbag cushion of claim
 7. 19. A vehicle restraint systemcomprising the airbag cushion of claim
 8. 20. A vehicle restraint systemcomprising the airbag cushion of claim
 9. 21. A vehicle restraint systemcomprising the airbag cushion of claim
 10. 22. A vehicle restraintsystem comprising the airbag cushion of claim 11.